Field of the Invention and Related Art Statement
The present invention relates to a method for automatic chemical analyzing and a reaction apparatus therefor. Particularly, the method and apparatus according to the invention are suitably used for judging hemolysis existing in a test liquid as well as analyzing the agglutination patterns produced in the test liquid in response to an immunological agglutination reaction.
There are two types of methods used for judging the agglutination pattern produced in response to an immunological agglutination reaction. One of them is a sedimentation method. In the sedimentation method, a sample and a reagent are delivered into a reaction vessel having a conical bottom surface and then centrifuged. Thereafter the reaction vessel is kept at a standstill to form a particle pattern to be analyzed on the conical bottom of the reaction vessel. The other method is a shaking method, in which the sample and reagent are delivered into a reaction vessel having a wine-cup shaped bottom surface and then centrifuged. Thereafter the reaction vessel is shaken in order to judge whether an agglutination reaction has occured in the test liquid.
In the sedimentation method, when the immunological agglutination reaction occurs in the test liquid, the blood cell particles are spread over the conical bottom surface of the reaction vessel to form an agglutination pattern thereon. When the immunological agglutination reaction does not occur in the test liquid, the blood cell particles slip down along the inner surface of the reaction vessel and gather at the center of the bottom surface to form a non-agglutination pattern thereat. These patterns formed on the bottom surface of the reaction vessel are shown in FIGS. 1A and 1B. Contrary to this, in the shaking method, when the immunological agglutination reaction has occured in the test liquid, the blood cell particles gather at the center of the wine-cup shaped bottom surface of the reaction vessel. When the immunological agglutination reaction does not occur in the test liquid, the blood cell particles are diffused into the test liquid as a whole. FIGS. 2A and 2B are side views illustrating these particle patterns formed in the reaction vessel by the shaking method.
When the hemolysis exists in the test liquid, the higher the degree of hemolysis, the higher the transparency of the test liquid. The test, liquid, having hemolysis to a high degree becomes the color of red ink, and even when the reaction vessel containing the test liquid is shaken, the transparency thereof does not change. On the other hand, the lower the degree of hemolysis, the lower the transparency of the test liquid, so that an object placed beyond the reaction vessel could not be seen through the test liquid.
Therefore, if hemolysis is caused in the test liquid by destroying the blood cells contained in the sample or reagent, the agglutination or nonagglutination patterns thereof could not be analyzed correctly. That is to say, if hemolysis exists in the test liquid, there is a fear that the non-agglutination pattern will be judged as an agglutination pattern in the segmentation method, and the agglutination pattern will be judged as a non-agglutination pattern in the shaking method. Therefore, it is necessary to check the existence of hemolysis in the test liquid prior to analyzing the particle pattern formed in the test liquid in order to obtain correct analyzing results.
Hitherto, the judgement of hemolysis was visually conducted by an operator before automatically analyzing the particle pattern formed in the test liquid by an analyzing apparatus. However, since the hemolysis reaction is very sensitive, skilled operators and many hours are required for judging. The visual judgement of the hemolysis lowers the analyzing efficiency of the automatic analyzing apparatus, and the visual judgement over many hours is apt to cause mistakes which affect the final judgement of the agglutination reaction in the test liquid.
Furthermore, there has not been suggested a special reaction apparatus suitable for use in the judgement of hemolysis existing in the test liquid, and thus, prior to the present invention, it was impossible to automatically judge hemolysis in the test liquid in the conventional analyzing apparatus.